The correct answer is: the treated glioblastoma cells were cultured in the presence of an inhibitor from umbilical cord stem cells, but the control cells were cultured without the inhibitor.
It has been shown that treatment with injected umbilical cord stem cells has strong therapeutic effects on glioma models. Those cells produce anti-tumour substances, with inhibitory effects.
Control group does not include the treatment in order to observe the treatment.
Genes involved in production of abnormal red blood cells may have an abnormal sequence of bases (nucleotides), like inherited alteration in the gene for JAK2, a protein with enzymatic activity that's linked to the abnormal production of blood cells.